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Advances in Experimental Medicine and... 2021Marfan syndrome (MFS) is a systemic connective tissue disorder that is inherited in an autosomal dominant pattern with variable penetrance. While clinically this disease... (Review)
Review
Marfan syndrome (MFS) is a systemic connective tissue disorder that is inherited in an autosomal dominant pattern with variable penetrance. While clinically this disease manifests in many different ways, the most life-threatening manifestations are related to cardiovascular complications including mitral valve prolapse, aortic insufficiency, dilatation of the aortic root, and aortic dissection. In the past 30 years, research efforts have not only identified the genetic locus responsible but have begun to elucidate the molecular pathogenesis underlying this disorder, allowing for the development of seemingly rational therapeutic strategies for treating affected individuals. In spite of these advancements, the cardiovascular complications still remain as the most life-threatening clinical manifestations. The present chapter will focus on the pathophysiology and clinical treatment of Marfan syndrome, providing an updated overview of the recent advancements in molecular genetics research and clinical trials, with an emphasis on how this information can focus future efforts toward finding betters ways to detect, diagnose, and treat this devastating condition.
Topics: Aortic Dissection; Aorta; Fibrillin-1; Humans; Marfan Syndrome; Transforming Growth Factor beta
PubMed: 34807420
DOI: 10.1007/978-3-030-80614-9_8 -
Revista Portuguesa de Cardiologia Apr 2020Marfan syndrome is an autosomal dominant connective tissue disease with an estimated incidence of 1 in 5000 individuals. In 90% of cases it is caused by mutations in the... (Review)
Review
Marfan syndrome is an autosomal dominant connective tissue disease with an estimated incidence of 1 in 5000 individuals. In 90% of cases it is caused by mutations in the gene for fibrillin-1, the main constituent of extracellular microfibrils. Studies on animal models of Marfan syndrome have revealed that fibrillin-1 mutations interfere with local TGF-β signaling, in addition to impairing tissue integrity. The cardinal features involve the cardiovascular, ocular and skeletal systems. The diagnosis of Marfan syndrome is made according to the revised Ghent nosology. Early identification and appropriate management are critical for patients with Marfan syndrome, who are prone to the life-threatening cardiovascular complications of aortic aneurysms and aortic dissection. The standard treatment includes prophylactic beta-blockers in order to slow down dilation of the ascending aorta, and prophylactic aortic surgery. The success of current medical and surgical treatment of aortic disease in Marfan syndrome has substantially improved mean life expectancy, extending it above 72 years. This review aims to provide an overview of this hereditary disorder.
Topics: Adrenergic beta-Antagonists; Aortic Dissection; Animals; Aorta; Aortic Aneurysm; Fibrillin-1; Marfan Syndrome; Mutation; Transforming Growth Factor beta
PubMed: 32439107
DOI: 10.1016/j.repc.2019.09.008 -
Nature Reviews. Disease Primers Sep 2021Marfan syndrome (MFS) is an autosomal dominant, age-related but highly penetrant condition with substantial intrafamilial and interfamilial variability. MFS is caused by... (Review)
Review
Marfan syndrome (MFS) is an autosomal dominant, age-related but highly penetrant condition with substantial intrafamilial and interfamilial variability. MFS is caused by pathogenetic variants in FBN1, which encodes fibrillin-1, a major structural component of the extracellular matrix that provides support to connective tissues, particularly in arteries, the pericondrium and structures in the eye. Up to 25% of individuals with MFS have de novo variants. The most prominent manifestations of MFS are asymptomatic aortic root aneurysms, aortic dissections, dislocation of the ocular lens (ectopia lentis) and skeletal abnormalities that are characterized by overgrowth of the long bones. MFS is diagnosed based on the Ghent II nosology; genetic testing confirming the presence of a FBN1 pathogenetic variant is not always required for diagnosis but can help distinguish MFS from other heritable thoracic aortic disease syndromes that can present with skeletal features similar to those in MFS. Untreated aortic root aneurysms can progress to life-threatening acute aortic dissections. Management of MFS requires medical therapy to slow the rate of growth of aneurysms and decrease the risk of dissection. Routine surveillance with imaging techniques such as transthoracic echocardiography, CT or MRI is necessary to monitor aneurysm growth and determine when to perform prophylactic repair surgery to prevent an acute aortic dissection.
Topics: Fibrillin-1; Fibrillins; Humans; Marfan Syndrome; Microfilament Proteins; Mutation
PubMed: 34475413
DOI: 10.1038/s41572-021-00298-7 -
Current Rheumatology Reports Nov 2021Marfan syndrome (MFS) is an autosomal dominant heritable disorder of fibrillin-1 (FBN1) with predominantly ocular, cardiovascular, and musculoskeletal manifestations... (Review)
Review
PURPOSE OF REVIEW
Marfan syndrome (MFS) is an autosomal dominant heritable disorder of fibrillin-1 (FBN1) with predominantly ocular, cardiovascular, and musculoskeletal manifestations that has a population prevalence of approximately 1 in 5-10,000 (Chiu et al. Mayo Clin Proc. 89(1):34-42, 146, Dietz 3, Loeys et al. J Med Genet. 47(7):476-85, 4).
RECENT FINDINGS
The vascular complications of MFS still pose the greatest threat, but effective management options, such as regular cardiac monitoring and elective surgical intervention, have reduced the risk of life-threatening cardiovascular events, such as aortic dissection. Although cardiovascular morbidity and mortality remains high, these improvements in cardiovascular management have extended the life expectancy of those with MFS by perhaps 30-50 years from an estimated mean of 32 years in 1972 (Dietz 3, Gott et al. Eur J Cardio-thoracic Surg. 10(3):149-58, 147, Murdoch et al. N Engl J Med. 286(15):804-8, 148). The musculoskeletal manifestations of MFS, which to date have received less attention, can also have a significant impact on the quality of life and are likely to become more important as the age of the Marfan syndrome population increases (Hasan et al. Int J Clin Pract. 61(8):1308-1320, 127). In addition, musculoskeletal manifestations are often critically important in the diagnosis of MFS. Here, we review the main clinically relevant and diagnostically useful musculoskeletal features of MFS, which together contribute to the "systemic features score" (referred to hereafter as systemic score), part of the revised Ghent nosology for MFS. We discuss current treatment strategies and highlight the need for a multidisciplinary approach to diagnosis and management. Finally, we review new pharmacological approaches that may be disease modifying and could help to improve the outcome for individuals with this syndrome.
Topics: Cardiovascular Diseases; Humans; Marfan Syndrome; Quality of Life
PubMed: 34825999
DOI: 10.1007/s11926-021-01045-3 -
Gene Oct 2016FBN1 encodes the gene for fibrillin-1, a structural macromolecule that polymerizes into microfibrils. Fibrillin microfibrils are morphologically distinctive fibrils,... (Review)
Review
FBN1 encodes the gene for fibrillin-1, a structural macromolecule that polymerizes into microfibrils. Fibrillin microfibrils are morphologically distinctive fibrils, present in all connective tissues and assembled into tissue-specific architectural frameworks. FBN1 is the causative gene for Marfan syndrome, an inherited disorder of connective tissue whose major features include tall stature and arachnodactyly, ectopia lentis, and thoracic aortic aneurysm and dissection. More than one thousand individual mutations in FBN1 are associated with Marfan syndrome, making genotype-phenotype correlations difficult. Moreover, mutations in specific regions of FBN1 can result in the opposite features of short stature and brachydactyly characteristic of Weill-Marchesani syndrome and other acromelic dysplasias. How can mutations in one molecule result in disparate clinical syndromes? Current concepts of the fibrillinopathies require an appreciation of tissue-specific fibrillin microfibril microenvironments and the collaborative relationship between the structures of fibrillin microfibril networks and biological functions such as regulation of growth factor signaling.
Topics: Animals; Disease Models, Animal; Fibrillin-1; Genetic Predisposition to Disease; Humans; Marfan Syndrome; Mutation
PubMed: 27437668
DOI: 10.1016/j.gene.2016.07.033 -
Zhongguo Dang Dai Er Ke Za Zhi =... Jul 2022Marfan syndrome (MFS) is a multisystem connective tissue disease with autosomal dominant inheritance. It is mainly caused by gene mutation and often has different... (Review)
Review
Marfan syndrome (MFS) is a multisystem connective tissue disease with autosomal dominant inheritance. It is mainly caused by gene mutation and often has different clinical manifestations. Neonatal MFS is especially rare with severe conditions and a poor prognosis. At present, there is still no radical treatment method for MFS, but early identification, early diagnosis, and early treatment can effectively prolong the life span of patients. This article reviews the latest advances in the diagnosis and treatment of MFS.
Topics: Fibrillin-1; Humans; Infant, Newborn; Marfan Syndrome; Mutation
PubMed: 35894201
DOI: 10.7499/j.issn.1008-8830.2203099 -
Proceedings of the National Academy of... Jun 2023Fibrillin-1 is an extracellular matrix protein that assembles into microfibrils which provide critical functions in large blood vessels and other tissues. Mutations in...
Fibrillin-1 is an extracellular matrix protein that assembles into microfibrils which provide critical functions in large blood vessels and other tissues. Mutations in the fibrillin-1 gene are associated with cardiovascular, ocular, and skeletal abnormalities in Marfan syndrome. Here, we reveal that fibrillin-1 is critical for angiogenesis which is compromised by a typical Marfan mutation. In the mouse retina vascularization model, fibrillin-1 is present in the extracellular matrix at the angiogenic front where it colocalizes with microfibril-associated glycoprotein-1, MAGP1. In mice, a model of Marfan syndrome, MAGP1 deposition is reduced, endothelial sprouting is decreased, and tip cell identity is impaired. Cell culture experiments confirmed that fibrillin-1 deficiency alters vascular endothelial growth factor-A/Notch and Smad signaling which regulate the acquisition of endothelial tip cell/stalk cell phenotypes, and we showed that modulation of MAGP1 expression impacts these pathways. Supplying the growing vasculature of mice with a recombinant C-terminal fragment of fibrillin-1 corrects all defects. Mass spectrometry analyses showed that the fibrillin-1 fragment alters the expression of various proteins including ADAMTS1, a tip cell metalloprotease and matrix-modifying enzyme. Our data establish that fibrillin-1 is a dynamic signaling platform in the regulation of cell specification and matrix remodeling at the angiogenic front and that mutant fibrillin-1-induced defects can be rescued pharmacologically using a C-terminal fragment of the protein. These findings, identify fibrillin-1, MAGP1, and ADAMTS1 in the regulation of endothelial sprouting, and contribute to our understanding of how angiogenesis is regulated. This knowledge may have critical implications for people with Marfan syndrome.
Topics: Animals; Mice; Extracellular Matrix; Fibrillin-1; Marfan Syndrome; Vascular Endothelial Growth Factor A
PubMed: 37252964
DOI: 10.1073/pnas.2221742120 -
Circulation May 2021Marfan syndrome (MFS) is an autosomal dominant disorder of the connective tissue caused by mutations in the (fibrillin-1) gene encoding a large glycoprotein in the...
BACKGROUND
Marfan syndrome (MFS) is an autosomal dominant disorder of the connective tissue caused by mutations in the (fibrillin-1) gene encoding a large glycoprotein in the extracellular matrix called fibrillin-1. The major complication of this connective disorder is the risk to develop thoracic aortic aneurysm. To date, no effective pharmacologic therapies have been identified for the management of thoracic aortic disease and the only options capable of preventing aneurysm rupture are endovascular repair or open surgery. Here, we have studied the role of mitochondrial dysfunction in the progression of thoracic aortic aneurysm and mitochondrial boosting strategies as a potential treatment to managing aortic aneurysms.
METHODS
Combining transcriptomics and metabolic analysis of aortas from an MFS mouse model () and MFS patients, we have identified mitochondrial dysfunction alongside with mtDNA depletion as a new hallmark of aortic aneurysm disease in MFS. To demonstrate the importance of mitochondrial decline in the development of aneurysms, we generated a conditional mouse model with mitochondrial dysfunction specifically in vascular smooth muscle cells (VSMC) by conditional depleting Tfam (mitochondrial transcription factor A; mice). We used a mouse model of MFS to test for drugs that can revert aortic disease by enhancing Tfam levels and mitochondrial respiration.
RESULTS
The main canonical pathways highlighted in the transcriptomic analysis in aortas from mice were those related to metabolic function, such as mitochondrial dysfunction. Mitochondrial complexes, whose transcription depends on Tfam and mitochondrial DNA content, were reduced in aortas from young mice. In vitro experiments in -silenced VSMCs presented increased lactate production and decreased oxygen consumption. Similar results were found in MFS patients. VSMCs seeded in matrices produced by Fbn1-deficient VSMCs undergo mitochondrial dysfunction. Conditional Tfam-deficient VSMC mice lose their contractile capacity, showed aortic aneurysms, and died prematurely. Restoring mitochondrial metabolism with the NAD precursor nicotinamide riboside rapidly reverses aortic aneurysm in mice.
CONCLUSIONS
Mitochondrial function of VSMCs is controlled by the extracellular matrix and drives the development of aortic aneurysm in Marfan syndrome. Targeting vascular metabolism is a new available therapeutic strategy for managing aortic aneurysms associated with genetic disorders.
Topics: Animals; Aortic Aneurysm; Disease Models, Animal; Humans; Marfan Syndrome; Mice; Mitochondria
PubMed: 33709773
DOI: 10.1161/CIRCULATIONAHA.120.051171 -
Genetics in Medicine : Official Journal... Jul 2017Genetic FBN1 testing is pivotal for confirming the clinical diagnosis of Marfan syndrome. In an effort to evaluate variant causality, FBN1 databases are often used. We...
BACKGROUND
Genetic FBN1 testing is pivotal for confirming the clinical diagnosis of Marfan syndrome. In an effort to evaluate variant causality, FBN1 databases are often used. We evaluated the current databases regarding FBN1 variants and validated associated phenotype records with a new Marfan syndrome geno-phenotyping tool called the Marfan score.
METHODS AND RESULTS
We evaluated four databases (UMD-FBN1, ClinVar, the Human Gene Mutation Database (HGMD), and Uniprot) containing 2,250 FBN1 variants supported by 4,904 records presented in 307 references. The Marfan score calculated for phenotype data from the records quantified variant associations with Marfan syndrome phenotype. We calculated a Marfan score for 1,283 variants, of which we confirmed the database diagnosis of Marfan syndrome in 77.1%. This represented only 35.8% of the total registered variants; 18.5-33.3% (UMD-FBN1 versus HGMD) of variants associated with Marfan syndrome in the databases could not be confirmed by the recorded phenotype.
CONCLUSION
FBN1 databases can be imprecise and incomplete. Data should be used with caution when evaluating FBN1 variants. At present, the UMD-FBN1 database seems to be the biggest and best curated; therefore, it is the most comprehensive database. However, the need for better genotype-phenotype curated databases is evident, and we hereby present such a database.Genet Med advance online publication 01 December 2016.
Topics: Databases, Factual; Databases, Nucleic Acid; Female; Fibrillin-1; Fibrillins; Genetic Association Studies; Genetic Testing; Genetic Variation; Genotype; Humans; Male; Marfan Syndrome; Microfilament Proteins; Mutation; Phenotype
PubMed: 27906200
DOI: 10.1038/gim.2016.181 -
International Journal of Environmental... Aug 2023Syndromic aortic diseases (SADs) encompass various pathological manifestations affecting the aorta caused by known genetic factors, such as aneurysms, dissections, and... (Review)
Review
Syndromic aortic diseases (SADs) encompass various pathological manifestations affecting the aorta caused by known genetic factors, such as aneurysms, dissections, and ruptures. However, the genetic mutation underlying aortic pathology also gives rise to clinical manifestations affecting other vessels and systems. As a consequence, the main syndromes currently identified as Marfan, Loeys-Dietz, and vascular Ehlers-Danlos are characterized by a complex clinical picture. In this contribution, we provide an overview of the genetic mutations currently identified in order to have a better understanding of the pathogenic mechanisms. Moreover, an update is presented on the basis of the most recent diagnostic criteria, which enable an early diagnosis. Finally, therapeutic strategies are proposed with the goal of improving the rates of patient survival and the quality of life of those affected by these SADs.
Topics: Humans; Ehlers-Danlos Syndrome, Type IV; Marfan Syndrome; Quality of Life; Aortic Diseases; Aorta
PubMed: 37623198
DOI: 10.3390/ijerph20166615